@article{1077473989, author = {Gustin, William}, title = {Sets of finite planar order}, journal = {Duke Math. J.}, volume = {14}, number = {1}, year = {1947}, pages = { 51-66}, language = {en}, url = {http://dml.mathdoc.fr/item/1077473989} }
Gustin, William. Sets of finite planar order. Duke Math. J., Tome 14 (1947) no. 1, pp. 51-66. http://gdmltest.u-ga.fr/item/1077473989/